This invention relates to an apparatus for applying traction to a limb of a patient. More particularly, the invention relates to a protective covering or drape for use, e.g., during surgery or the like, on the patient's limb to apply traction.
During surgery, e.g., arthroscopic surgery, or the like, it may be necessary to apply traction to a limb of the patient. Various systems for applying such traction have been suggested and used. Certain of these prior systems have focused all of the traction force on one relatively small area of the limb, with the result that the small area becomes injured. For example, a system for applying traction to an arm may apply the force to the wrist, and cause a wrist injury. Additionally, the traction force might not be evenly applied, which can also result in injury to the limb.
Another concern regarding surgical or the like procedures is that of maintaining the sterile field. Thus, it is important that the limb being placed in traction does not contaminate the sterile field, e.g., within the operating room, and is not contaminated by microbes which may exist in the operating room. It is advantageous to protect or isolate the limb under traction with a surgical drape which is microbially impermeable.
Casperi U.S. Pat. No. 4,679,552 discloses a surgical drape for a limb in traction. A two layer sleeve is disclosed with an inner layer of soft textile material and an outer layer of moisture impermeable sheet material, such as a thin sheet of latex. Traction pads are stitched to the interior of the two layer sleeve. The traction force is applied to these traction pads which contact the limb so that the force is distributed along the contact area between the traction pads and the limb. Although Casperi does reduce the concentration of traction force to some extent, this force is not uniformly distributed around the periphery of the limb. Also, although water impermeable latex is used, it is repeatedly stitched through in fabricating the surgical drape. Such stitches or punctures reduces the usefulness of the latex as a sterile barrier.
A number of medical devices have been suggested using a component of a contractible material and construction such as that used in what is commonly known as a "Chinese Finger Trap". Such component is adapted to contract about, and often grip at least to some extent, an object inserted in the component whenever an attempt is made to withdraw the object therefrom. See, for example, Trott U.S. Pat. No. 2,783,758; Giannestras U.S. Pat. No. 3,390,675 and Tammy, et. al. U.S. Pat. No. 3,872,861. However, each of these patents involved holding only a thumb, toe or finger, so that even distribution of traction forces over a relatively large area was not an issue. Also, none of these patents are concerned with maintaining a sterile barrier.